B Why did famous people think consciousness causes collapse?

[maline]

By Bell theorem, realism leads to non-locality. For some reason, many people don't like non-locality. That's why they consider non-realism and the role of consciousness

This partially explains the tendency towards non-realism (whatever that means), perhaps including Wheeler's conception. It does not apply to Von Neumann's "consciousness causes collapse"- that is a fully realistic model, in which consciousness plays a causative (and nonlocal) role.

Before commenting it might be wise to look at an actual consciousness causes collapse proposal eg Penrose:
https://plato.stanford.edu/entries/qt-consciousness/#4.5

Penrose is not a supporter of "consciousness causes collapse". He has his different ideas, in which a realist collapse is caused by quantum gravity effects. He proposed that these effects are used in the brain to produce consciousness and understanding- not the other way round.

 

[DrChinese]

As a measure requires the existence of someone who performs the measure, so then the question of whether consciousness is to collapse the wave function becomes relevant ...

There are experiments in which there are conscious observers, and collapse; and there are others also with conscious observers, but NO collapse. So apparently that (consciousness) is not the variable at play.

 

[TJung]

others also with conscious observers, but NO collapse. So apparently that (consciousness) is not the variable at play.

Could you provide that?
Thanks.

TJung

 

[rootone]

What about if the measurement is done with NO conscious observer, but is instead recorded by automation and left alone for a while?
Then some time later the recording is examined independently by several observers who had nothing to do with the experiment ...
Will all these observers agree on what was recorded?
It seems improbable that they would have differing opinions of the recording, in which case consciousness is irrelavent

 

[TJung]

What about if the measurement is done with NO conscious observer, but is instead recorded by automation and left alone for a while?
Then some time later the recording is examined independently by several observers who had nothing to do with the experiment ...
Will all these observers agree on what was recorded?

Isn't this how all experiments are done? A apparatus records the results and shows to the observer (human being) in a screen. Does it matters if it took 10ns or 24h to the observer watch the results?

 

[rootone]

I mean if the person who performed the experiment is not an observer.
They are replaced by other observers who had nothing to do with the experiment.
Perhaps the original experimenter could be no longer alive when the recording is examined.

 

[TJung]

I mean if the person who performed the experiment is not an observer.
They are replaced by other observers who had nothing to do with the experiment.
Perhaps the original experimenter could be no longer alive when the recording is examined.

Ok, you are trying to test if the experiment gets a different result if it is watched by someone who designed it or not. You could do that, I don't think it will make any difference.

 

[DrChinese]

Could you provide that?
Thanks.

TJung

http://sciencedemonstrations.fas.ha...-demonstrations/files/single_photon_paper.pdf

An apparatus for a double-slit interference experiment in the single-photon regime is described. The apparatus includes a which-path marker that destroys the interference as well as a quantum eraser that restores it. We present data taken with several light sources, coherent and incoherent and discuss the efficacy of these as sources of single photons.

 

[Karolus]

Ok, you are trying to test if the experiment gets a different result if it is watched by someone who designed it or not. You could do that, I don't think it will make any difference.

Right.
to to reinforce the concept, I quote from
The Feynman lectures on Physics. Vol.3
Chapter 3-2: The two-slit interference pattern:

"Now we would like to emphasize an important point so that you will avoid a common error. ...
At the end of the process you may say that you "don't want to look at the photon" That's your business, but you still do not add the amplitudes. Nature does not know what you are looking at, and she behaves the way she is going to behave the way she is going to behave whether you bother to take down the data or not."

 

[bhobba]

Penrose is not a supporter of "consciousness causes collapse". He has his different ideas, in which a realist collapse is caused by quantum gravity effects. He proposed that these effects are used in the brain to produce consciousness and understanding- not the other way round.

That is NOT what the link I gave says:
With respect to the neurophysiological implementation of Penrose's proposal, his collaboration with Hameroff has been crucial. With his background as an anaesthesiologist, Hameroff suggested to consider microtubules as an option for where reductions of quantum states can take place in an effective way, see e.g., Hameroff and Penrose (1996). The respective quantum states are assumed to be coherent superpositions of tubulin states, ultimately extending over many neurons. Their simultaneous gravitation-induced collapse is interpreted as an individual elementary act of consciousness. The proposed mechanism by which such superpositions are established includes a number of involved details that remain to be confirmed or disproven.

But as I said its quite sophisticated.

Thanks
Bill

 

[TJung]

http://sciencedemonstrations.fas.ha...-demonstrations/files/single_photon_paper.pdf

An apparatus for a double-slit interference experiment in the single-photon regime is described. The apparatus includes a which-path marker that destroys the interference as well as a quantum eraser that restores it. We present data taken with several light sources, coherent and incoherent and discuss the efficacy of these as sources of single photons.

Very good article, thank you! A classic quantum erasure experiment, but very well explained.
But I don't see how you can say for sure that there isn't any conscious observer in this experiment collapsing the wave-function.

TJung

 

[bhobba]

But I don't see how you can say for sure that there isn't any conscious observer in this experiment collapsing the wave-function.

I am not an experimental type person so maybe I am missing something. But I did notice the camera at the end of the apparatus.

Thanks
Bill

 

[low inhibition]

Right.
to to reinforce the concept, I quote from
The Feynman lectures on Physics. Vol.3
Chapter 3-2: The two-slit interference pattern:

"Now we would like to emphasize an important point so that you will avoid a common error. ...
At the end of the process you may say that you "don't want to look at the photon" That's your business, but you still do not add the amplitudes. Nature does not know what you are looking at, and she behaves the way she is going to behave the way she is going to behave whether you bother to take down the data or not."

i read feyman's popular book https://en.wikipedia.org/wiki/QED:_The_Strange_Theory_of_Light_and_Matter

he makes the point that as long as u don't try to obtain "information" about the particle, no collapse happens. but when u do try to obtain information, it collapse. he suggested multiple times that nature is conspiring against us.

however he never mentioned anything about consciousness cause collapse.

i think when u try to obtain information u have to send a photon to detect the particle, this CHANGES it. so the act of observation influences the particle, it shouldn't be that surprising that nature is "conspiring" against us. its just like how absolute zero can never be achieved, even though in classical physics its possible in principle.

i think its ridiculous to think consciousness causes collapse, because consciousness didn't even exist for most of the history of the universe, and the universe was working just fine back then, and even now when we aren't looking at quasars billions of light years away. unless u buy into that panpsychism thing, which i find ridiculous. i used to be a substance dualists btw, now a property dualist, I am not some hardcore materialist spouting nonsense that consciousness/qualia don't exist.

 

[Nugatory]

This thread has shifted from the original question ("Why did some very smart and capable people, working with the knowledge available to them early last century, seriously consider the possibility that consciousness causes collapse?") into "Given what we know now, is it not ridiculous to claim that consciousness causes collapse?"

As we're no longer on the original question, this thread is closed. If you would like to contribute something more to it and have considered that the audience will be someone who finds the thread through a search a few years from now, PM me or any other mentor to have the thread reopened for your post.